The present invention relates to a light-weight miniature liner guide device which is suitable for relatively small equipment such as equipment concerning computers, OA (office amenity) equipment and measuring equipment.
A conventional miniature linear guide device is for instance as shown in FIGS. 18 and 19. The linear guide device is made up of a guide rail 1 substantially U-shaped in section which is extended in a longitudinal direction (or axial direction) of the device, and a slider 2 slidably mounted on the guide rail 1. The slider 2 provides: a slider body 3 U-shaped inversely in section which is formed of a thin steel plate by pressing; a circulator 4 which is formed of plastic by molding and has ball circulating paths therein; and a cap 5 which is formed of plastic. The circulator 4 and the cap 5 are fitted in a concave portion of the slider body 3 in such a manner that the cap 5 is interposed between the slider body 3 and the circulator 4.
Load ball rolling grooves 1B and 3B are formed in the inner surfaces of both side walls of the guide rail 1 and in the outer surfaces of both side walls of the slider body 3, respectively, in such a manner that those grooves 1B and 3B are extended in an axial direction of the guide device and confronted with each other. A number of balls 6 are fitted in the load ball rolling grooves 1B and 3B and in the ball circulating paths in the circulator 4. The balls 6 are infinitely circulated while being rolled so that the slider 2 is linearly moved along the guide rail 1.
The above-described conventional linear guide device suffers from the following difficulties:
The linear guide device has been provided with the premise that it is used in a clean atmosphere, for instance in a clean room which is substantially free from dust; that is, it is not protected from dust. Hence, if it is used in an atmosphere other than a clean atmosphere, then dust enters the linear guide device, thus adversely affecting the operation of the linear guide device.
On the other hand, lubricant such as grease and lubricating oil are liable to scatter out through the gaps between the guide rail and the end faces of the slider engaged with the guide rail. This makes the linear guide device insufficient in lubrication, thus decreasing the service life of the linear guide device.